In the gas sample conditioning field, particularly when dealing with cryogenic liquids such as LNG, heat generated within a vaporizer can migrate up-stream of the vaporizer entry port and along the sample conduit tubing employed to communicate a cryogenic liquid sample from its source. (i.e., a pipeline) into the sample conditioning cabinet. Such heat energy migration has the undesirable effect of causing sample pre-vaporization before introduction of the extracted liquid sample into the vaporizer. Pre-vaporization of an incoming sample adversely impacts the accuracy of a sample analysis thereof by, for example, creating phase and fluid component partitioning within the sample, interfering with uniform sample flow into the vaporizer, and/or generating sufficient back-pressure to create a deadheading effect within the system. In the event any of the foregoing occur, the accuracy of any analysis, i.e., quantifying the energy content of a particular LNG sample, becomes suspect.